选择SD大鼠48只, 随机分为6组(n=8): 分别为正常对照组(N组)、内毒素模型组(LPS组)、高、中、低剂量右旋美托咪定组(HD组、MD组、LD组)及育亨宾拮抗组(YHB组)。静脉注射内毒素 4 mg/kg复制大鼠急性肺损伤模型后, LD、MD及HD组分别立即注射相右旋美托咪定0.5μg/kg、1.5μg/kg及4.5μg/kg, YHB组则在Dex 4.5μg/kg基础上另注射育亨宾0.1 mg/kg, N组注射同等剂量的生理盐水。6 h后处死动物, 测定肺湿重/干重比、肺组织NF-κB、TLR4 mRNA的表达, 肿瘤坏死因子-α、白介素-1β和白介素-6的含量, HE染色光镜观察肺组织病理变化英语翻译。

48 SD rats were selected and randomized into six groups (n=8): the normal control group (N group) and the Lipopolysaccharide model group (LPS group), the Dexmedetomidine groups in high, moderate and low dosages (HD group, MD group and LD group) as well as yohimbine antagonizing group (YHB group). After the acute lung injury model of rats was duplicated after intravenous injection with 4 mg/kg Lipopolysaccharide, the rats in LD, MD and HD groups were immediately injected with 0.5 μg/kg, 1.5 μg/kg and 4.5 μg/kg Dexmedetomidine respectively, while the rats in the YHB group were induced with 0.1 mg/kg yohimbine besides the injection with 4.5 μg/kg Dex, and the rats in the N group were injected with the same dosage of physiological saline. The animals were killed after 6 h and the ratio of humid weight and dry weight of lung tissues, NF-κB and TLR4 mRNA expression in lung tissues, contents of tumor necrosis factor-α, interleukin-1β and interleukin-6, and HE staining was carried out observe the pathological changes in lung tissues under a light microscope.

与LPS组比较, MD和HD组不同程度抑制肺组织NF-KB和TLR4 mRNA的表达、减少肿瘤坏死因子-α、白介素-1β和白介素-6的含量及肺湿重/干重比(P<0．05), 光镜下可见肺组织损伤明显减轻。LD组上述指标改善不明显法语口译。

in comparison to the results from the LPS group, NF-κB and TLR4 mRNA expression in lung tissues in MD and HD groups were inhibited in different degrees, contents of tumor necrosis factor-α, interleukin-1β and interleukin-6 as well as the ratio of humid weight and dry weight of lung tissues were reduced (P<0.05), and it can be found that the injuries in lung tissues were significantly alleviated under the light microscope. The improvements in the indexes as mentioned above in LD group were not obvious.